Commit 7e7797e7 authored Mar 22, 2011 by Johan Hovold Committed by Greg Kroah-Hartman Mar 23, 2011

USB: cdc-acm: fix potential null-pointer dereference on disconnect



Fix potential null-pointer exception on disconnect introduced by commit
11ea859d (USB: additional power savings
for cdc-acm devices that support remote wakeup).

Only access acm->dev after making sure it is non-null in control urb
completion handler.

Cc: stable <stable@kernel.org>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent 15e5bee3

drivers/usb/class/cdc-acm.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -297,6 +297,8 @@ static void acm_ctrl_irq(struct urb *urb)
		if (!ACM_READY(acm))
		goto exit;

		usb_mark_last_busy(acm->dev);

		data = (unsigned char *)(dr + 1);
		switch (dr->bNotificationType) {
		case USB_CDC_NOTIFY_NETWORK_CONNECTION:
		@@ -336,7 +338,6 @@ static void acm_ctrl_irq(struct urb *urb)
		break;
		}
		exit:
		usb_mark_last_busy(acm->dev);
		retval = usb_submit_urb(urb, GFP_ATOMIC);
		if (retval)
		dev_err(&urb->dev->dev, "%s - usb_submit_urb failed with "